1. Field of the Invention
The present invention relates to a reluctance motor, in which a rotor is so formed as to have portions having different magnetic permeabilities alternately located in the circumferential direction, therein creating the interaction with the magnetic field by the difference in the magnetic pearmeabilities, and the reluctance motor is rotated by this interaction.
2. Description of the Prior Art
FIG. 14 is an exploded view for explaining the operating principle of a reluctance motor. A magnetic pole 12 is formed in a stator 10, and a coil 13 is formed by winding conductors in concentration around a magnetic pole. An AC current of established phase is respectively supplied at the three phases of U, V and W to the corresponding portions of the coil 13, and the magnetic poles wound with respective coils are respectively excited by U, V and W phases. Hereinafter, when explaining the phases of a magnetic pole 12 and the coil 13 distinguishably, letters indicating the phase will be attached after each code for the purposes of explanation, such as magnetic pole 12-U and coil 13-U. At a rotor 16, two salient poles 18 are arranged for three magnetic poles 12-U, 12-V and 12-W of a stator. In the explanation hereinafter, if it becomes necessary to describe each salient pole separately from the others, then a hyphen and a number such as -1, -2 or -3 will be attached to each salient pole starting from the head of the rotating direction, as shown in the drawings.
When the phase is 0.degree., the magnetic poles 12-V and 12-W are excited, and magnetic flux is created between these 2 magnetic poles and salient poles 181- and 18-2 as shown by a dashed line on the drawings. At this time, an attractive force acts (shown by arrows on the drawings) between the magnetic pole 12-V and the salient pole 18-2, and the rotor 16 rotates clockwise. When the phase is 30.degree., the magnetic poles 12-U, 12-V and 12-W are excited, and the salient pole 18-2 facing the magnetic pole 12-V is located almost at the front, so that no torque is generated here and a torque is generated in other magnetic poles 12-U and 12-W. In this way, the rotor as a whole is rotated while the position of the magnetic flux sequentially created is changing.
In the reluctance motor described above, the relative position of the magnetic pole 12 and the salient pole 18 is deviated as the rotor 16 is rotated therefore, the direction of the magnetic flux inside the magnetic pole 12 and the salient pole 18 has a component in the circumferential direction, and even the magnitude of this component will vary. By this variation in the component in the circumferential direction, there was such a problem that the efficiency and the output could not be enhanced since iron loss increased. In other words, it was not possible to improve the compactness of the motor at all.